The P-16 Combat Armor suit has been for decades the prime combat uniform for Caledonian troops. The P-16 is also the standard infantry armor kit for troops in the armed forces of the Confederacy of Duncinae.

The P-16 was developed by Pirbright Systems Ltd as a private venture. It was quickly seen to be vastly superior to existing Caledonian protective wear and adopted by the military.

The original P-16 consisted of a full-body coverall combining a layer of "Arquebus" flexible-ceramic armor combined with MAS (Crysteel) plates situated over vital organs. The overall includes a Load-Bearing Web (LBW) with modular pouches holding first aid kits, navigation gear and connectors for ammunition pouches. It also includes a body generator, generating electrical power from the movement of the wearer. The outer layer includes an ablative element against energy weapons.

As technology levels and threats advanced (to TL–12), Pirbright undertook a major redesign of the P16 system.

The overall included a layer of "Matchlock" fluid-ceramic responsive armor, enabling the armor to respond to kinetic impacts as they occurred while not impeding mobility. Composite plates of MAK (Molecularly-Aligned Ceramic) laminated with MAT (molecularly-aligned titanium), for increased protection against energy weapons as well as kinetic impact - were placed over vital areas, increasing protection from the earlier Crysteel plates while reducing the weight. The outer layer was also "Chameleon"-fitted, automatically presenting a thermal signature identical the the background. The P19 helmet was built of a non-reactive MAK/MAT laminate.

Designed for vehicle crews and other troops working in confined spaces, the helmet was smaller, the strike plates replaced with an additional layer of "Matchlock", and PCG pack frame replaced with a smaller, lighter PCL frame.